The invention relates to a heating system for a motor vehicle with an air-cooled rear engine of the type including a heating pipe of a heating line provided with a sound absorbing device extending inside body parts of the motor vehicle.
In a known heating system of the initially mentioned type disclosed in German Published Unexamined Patent Application (DE-OS) 16 30 919, the heating pipes equipped with sound absorbing devices are housed inside body parts (protuberances) of the motor vehicle and are fixedly connected with it, these body parts, together with the heating pipes, being subjected to a subsequent surface treatment. The heating pipes, which are made of steel tubing, are welded together with the body parts. So that no paint can enter the sound absorbing device for example, during dip painting, the inflow and outflow openings of the sound absorbing device are provided with inserted coverings which can be removed after the conclusion of the surface treatment. In practice, it was found that, despite these coverings, paint partly enters into the sound absorbing device which results in an annoying odor in the passenger space. In these cases, time-consuming and cost-consuming measures (such as a rinsing of the sound absorbing device) are required in order to eliminate this annoying odor. In addition, in the case of this arrangement, a defective sound absorbing device can be replaced only at high cost--removal of the outside plate of the protuberance.
It is an object of the invention to take such measures at the vehicle body and at the heating system that, on the one hand, a simple low-cost mounting of the heating pipe and an exchange of a defective sound absorbing device is ensured and that, on the other hand, an annoying odor from the sound absorbing device because of the surface treatment of the motor vehicle is avoided.
According to the invention, this object is achieved by providing an arrangement wherein the heating line with the integrated sound absorbing device is formed by a prefabricated flexible mounting part which, after the surface treatment of the motor vehicle, is inserted in the body part through a mounting opening provided in a front wheel house and at the end face is connected with adjacent components of the heating system and of the body.
Principal advantages achieved by means of especially preferred embodiments of the invention are that, as a result of the flexible construction of a prefabricated corrugated-tube-type mounting part consisting of a sound absorbing device, an elbow and a corrugated-tube hose, a simple and low-cost mounting and demounting of the heating pipe which extends inside a body part is achieved. A defective sound absorbing device can be exchanged easily and rapidly in this arrangement. As a result of the mounting of the heating pipe after the surface treatment, the paint cannot come in contact with the sound absorbing device and thus can also not cause any annoying odor. In certain preferred embodiments, the sound absorbing device is fixed in its installed position by means of spring clips introduced into the side member of the vehicle. The end connection piece arranged at the rear end of the corrugated-tube hose permits an easy suspending of the steel cable as well as a simple connection between the corrugated-tube hose and the rear transition piece.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.